FILE PHOTO: Facebook logo is seen at a start-up companies gathering at Paris' Station F in Paris, France on January 17, 2017. REUTERS/Philippe Wojazer/File Photo

Sandberg, the No. 2 executive at the world’s largest social media network, took a break from answering questions about privacy and Facebook’s role in elections to address what she called an important moment for women given recent scandals over sexual harassment.

“Go back and be loud and clear, especially if you are a male, that you are committed to mentoring women. It will make a huge difference,” Sandberg said at the Morgan Stanley 2018 Technology, Media & Telecom Conference.

Sandberg, 48, published a memoir about female empowerment, “Lean In,” in 2013. It became a bestseller and ignited debate over women’s opportunities in the professional world.

It was not immediately clear how the audience reacted. Morgan Stanley barred media from the conference, although it allowed Facebook to broadcast audio on an investor website.

Sandberg, near the close of her appearance, said she wanted to use the remaining time to address a topic no one had asked about. “Investors, you guys have a lot of power,” she said.

She cited survey research that said nearly half of male managers feared meetings with junior female colleagues, even as they accepted meetings with male colleagues. The result is unequal, she said.

If managers “don’t feel comfortable having dinner with women, then they shouldn’t have dinner with men,” Sandberg said.